降低OFDM系统PAPR的改进方法与性能分析

针对编码后的OFDM信号的PAPR的降低问题,提出了一种利用改进的选择映射(SLM)方法处理的OFDM信号进行限幅处理的新方法来降低PAPR,即改进的畸变SLM算法.该算法把相位序列信息嵌入在编码后的OFDM数据块的检测符号上,从而避免了数据传输速率的损失,限幅的使用更加有效地降低了PAPR.通过对新方法的计算机仿真结果说明,这种方法可以在不增加系统误码性能的基础上,获得比普通的SLM技术更好的降低PAPR的性能.

An Improved Method to Reduce PAPR of OFDM System and Its Performance Analysis

Due to its special modulating characteristics,the orthogonal frequency division multiplexing(OFDM) technique results in a high peak-to-average power ratio(PAPR).The high PAPR signal to power amplifier needs strict linearity,and it thus becomes the main obstacle for OFDM technique to be applied in practice.An improved SLM selected mapping method is therefore put forward to reduce PAPR of OFDM system.The phase sequence is required to be embedded in the check operators of the OFDM data block so as to avoid the data transmission rate loss and reduce PAPR more efficiently by clipping.A computer simulation was done with the improved method and the results proved that it can reduce the PAPR of OFDM system more than conventional SLM technique with no code errors increased.